Massive clanging noise and scraping while rotating the eng

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Jivermo
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Re: Massive clanging noise and scraping while rotating the e

Post by Jivermo » Mon Dec 07, 2015 6:21 pm

I agree. The stud face looks polished by the rubbing, and you can see metal chips in the shroud indentation and below the stud.

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Amskeptic
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Re: Massive clanging noise and scraping while rotating the e

Post by Amskeptic » Mon Dec 07, 2015 6:42 pm

Ronin10 wrote:Looks like it was the fan grinding against the fan shroud.
Forensics my boy, forensics . . .

a) assume that a stationary part came out and met the fan.
b) assume that the #1 thrust bearing completely gave up the ghost and gives .020" additional end play of all of a sudden and allowed the crankshaft fan to bang back and forth so far that it found the stud.

Chances are . . . .

a) stud backed out. The differential diagnosis in this case is the smooth wear on the fan. If it were b, it would be more haphazard.
Did you note how easily (or difficult) the fan housing nuts loosened? Was the bottom left different than the others? Did it have aluminum shards in its threads? Can you determine why this event occurred?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Ronin10
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Re: Massive clanging noise and scraping while rotating the e

Post by Ronin10 » Mon Dec 07, 2015 11:30 pm

I can't believe no one excoriated me for the leaking seal behind the fan hub!

Got back into the garage a bit after ticking nieces and nephews off the gift list. Yes, that fan shroud mounting stud at the 7:00 position was ground down while the others were untouched. I checked the torque on the shroud nuts and all were quite loose though the bottom left and top right were the loosest which correlates to the wear on the shroud. I tightened them down snug, but couldn't find an official torque after searching my Bentley. Feel free to pipe in if you know.

It's bedtime so I didn't check to see if the stud had backed out, figuring I should remove the shroud altogether before double nutting the stud to see if I can thread it deeper into the case. A check for tomorrow.

A question though...the fan was balanced with the rest of the rotating assembly. Obviously, that has now been disturbed. I do have a spare. Do I clean up the current fan or use the spare?

I'm pretty confident once I take care of the stud and correctly torque down the shroud, I'll be able to run normally again. Of course, another issue revealed itself too:
Image

Those boots are less than 18 months old and have less than 10k miles on them. Happened on the other side too. I have spares, but still! Annoying.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

Jivermo
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Re: Massive clanging noise and scraping while rotating the e

Post by Jivermo » Tue Dec 08, 2015 6:49 am

That's rough. Were they Rein brand? I just refurbished my CV joints, using Rein, and I would prefer not to do that work again for a couple of years. It appears that here is no grease left to lube the joint, and grit has easy entry to the machined surfaces. The original boots by VW lasted for many years. Man, when we can't get a quality reproduction of something as simple as this, it's quite disheartening.

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Amskeptic
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Re: Massive clanging noise and scraping while rotating the e

Post by Amskeptic » Tue Dec 08, 2015 7:24 am

Jivermo wrote:That's rough. Were they Rein brand? I just refurbished my CV joints, using Rein, and I would prefer not to do that work again for a couple of years. It appears that here is no grease left to lube the joint, and grit has easy entry to the machined surfaces. The original boots by VW lasted for many years. Man, when we can't get a quality reproduction of something as simple as this, it's quite disheartening.
Ronin10, do not worry about the balance of the fan if it is worn consistently around the circle.
Torque value (in the Bentley) is 14 ft/lbs.

Jivermo, I have 50,000 miles on my Reins, they are fine. (I also have the factory original BobD boots sitting on Road Warrior axle shafts with approximately 75,000 miles and 38 years on them, and they are fine.

We. have. to. bitch. politely. for. better. quality.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Ronin10
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Re: Massive clanging noise and scraping while rotating the e

Post by Ronin10 » Tue Dec 08, 2015 12:39 pm

These were Reins for what it's worth. Though Seattle streets might as well be off road. The inner boots are fine so I'll leave those. The spares I have are lobro, so hopefully they'll hold up.

Scoring on the hidden face of the fan pulley from the protruding screw is pretty uniform, but the perimeter wear gettin contacting the shroud is a little uneven, limited to about a 120 deg arc, but seems to be paint mostly.

I saw 14 ft lbs in the Bentley for fan to hub, assumed these would be the same since the shroud to case studs are 8mm as well, but want sure. Thanks.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

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Bleyseng
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Re: Massive clanging noise and scraping while rotating the e

Post by Bleyseng » Tue Dec 08, 2015 7:53 pm

Yeah, I have problems here in Seattle blowing out the CV boots with the huge pot holes and weather.
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
http://bleysengaway.blogspot.com/

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Amskeptic
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Re: Massive clanging noise and scraping while rotating the e

Post by Amskeptic » Tue Dec 08, 2015 8:13 pm

Bleyseng wrote:Yeah, I have problems here in Seattle blowing out the CV boots with the huge pot holes and weather.
It is not pot holes. It is actually more arcane than that.

a) the grease should remain mostly in contact with the CV components. Some of these boots have a grease dam to keep it up near the CV. Boots fully greased down to the driveshafts seem to rot out.

b) you actually do need to adjust/trim the quantity of air in the boot for those well-lubricated CV joints that are air-tight. I had boots that ballooned mightily in the heat, and I have had boots that dimpled in the chill.
Dimpling will tear any pleat in short order.

c) SO FAR, my experiment on Chloe ( occasionally washing the boots with mild soap and water ) has proven to keep them in decent shape.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Ronin10
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Re: Massive clanging noise and scraping while rotating the e

Post by Ronin10 » Tue Dec 08, 2015 11:15 pm

Verified that the lower left stud for the fan shroud was indeed loose. Spent most of the evening extracting the shroud, but I took care of some oil leaks too...this case has a mechanical fuel pump mounted to it which was leaking so I replaced the gaskets on that and then the aforementioned leak at the main seal behind the fan. I had to get creative with pulling the fan hub:Image

On the CV boots, Colin, what kind of volume ratio do you recommend between grease to air? Also, if you recall, these are the boots we replaced on your first visit two summer's ago, when we did the trans.

Lastly, as a point of interest, the day before the hellbent clanging, I went to a nearby junkyard and salvaged some parts, one of which was an old timing scale:Image

I don't know if it's original or not, but it's metal with painted timing marks. That's my current timing scale with it. When I align the mounting holes, there a 2-3 degree difference in "0". I tried to show that as best as possible in the photo, but the difference is a bit exaggerated (maybe 1/2 a degree) due to the offset.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

Jivermo
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Re: Massive clanging noise and scraping while rotating the e

Post by Jivermo » Wed Dec 09, 2015 1:05 am

Is it in that box in the back?

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Ronin10
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Re: Massive clanging noise and scraping while rotating the e

Post by Ronin10 » Wed Dec 09, 2015 10:29 am

Sorry, I don't have a computer at home at the moment and was posting via my phone. Fixed it, see above.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

Jivermo
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Re: Massive clanging noise and scraping while rotating the e

Post by Jivermo » Wed Dec 09, 2015 12:36 pm

Nice numbers on that thing. Must be original German; the new stuff is not going to look that good.

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Ronin10
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Re: Massive clanging noise and scraping while rotating the e

Post by Ronin10 » Wed Dec 09, 2015 12:47 pm

I might run it if the consensus is that it's original, but I'll have to perma-mark it somehow to replicate key timing positions as I could rub the pain off with my fingernails.
Oscar: 1976 Sage Green Bus, Stock Motor, Solid Lifters, Manual Transaxle

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Bleyseng
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Re: Massive clanging noise and scraping while rotating the e

Post by Bleyseng » Wed Dec 09, 2015 1:17 pm

Amskeptic wrote:
Bleyseng wrote:Yeah, I have problems here in Seattle blowing out the CV boots with the huge pot holes and weather.
It is not pot holes. It is actually more arcane than that.

a) the grease should remain mostly in contact with the CV components. Some of these boots have a grease dam to keep it up near the CV. Boots fully greased down to the driveshafts seem to rot out.

b) you actually do need to adjust/trim the quantity of air in the boot for those well-lubricated CV joints that are air-tight. I had boots that ballooned mightily in the heat, and I have had boots that dimpled in the chill.
Dimpling will tear any pleat in short order.

c) SO FAR, my experiment on Chloe ( occasionally washing the boots with mild soap and water ) has proven to keep them in decent shape.
Colin
So far it happened on all the cars- 04Passat, 914, Ghia and Westy. Yup I try to wash em and keep them clean and grease is only by the CV joint and I do not fill the rubber boot with grease.
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
http://bleysengaway.blogspot.com/

phaedrus76
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Re: Massive clanging noise and scraping while rotating the e

Post by phaedrus76 » Wed Dec 09, 2015 9:23 pm

Ronin10 wrote:I might run it if the consensus is that it's original, but I'll have to perma-mark it somehow to replicate key timing positions as I could rub the pain off with my fingernails.
I believe the original timing scale for your '76 is made of black plastic. I can vouch for the accuracy of the repros, but using one and painting the raised numbers and marks white makes for a very readable scale.
76 Sage Green Deluxe Westy w/ manual trans.

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